"I've studied various schools of thought... I acknowledge that some Muslims consider music prohibited, but I've found a lot of evidence from the life of the Prophet to show that he allowed certainly, but even encouraged, music at certain times"

This quote by Cat Stevens suggests that he has actually studied different schools of idea and has concerned the conclusion that music is not forbidden in Islam. He acknowledges that some Muslims consider music to be prohibited, however he has actually discovered evidence from the life of the Prophet to reveal that he allowed and even encouraged music at particular times. This suggests that Stevens has actually done his research and has concerned the conclusion that music is not prohibited in Islam. He is likely trying to motivate others to look into the proof and concern their own conclusions. This quote shows that Stevens is open-minded and happy to take a look at various point of views and evidence before forming his own opinion.